Trestle



E. F. GREEN Jan. 17, 1933.

TRESITLE Filed Sept. 19. 1929 Patented Jan. 17, 1933 UNITED STATESPATENT OFFICE,

EARL F. GREEN, or YORK, PENNSYLVANIA, ASSIGNOR TO THE MANLEY MANUrAc-TUBING COMPANY, or YORK, PENNSYLVANIA, .A CORPORATION or DELAWARE'IYRESTLE Application filed September 19, 1929. Serial No. 393,742.

I This invention relates totrestles and has for its object thesimplification of such trestles particularly those intended for holdingautomobiles while being repaired or serviced. A further prime objectofthe invention is the provision of a unitary handle and pawl casting bymeans of which the trestle can expeditiously be carried away by a singlemotion which simultaneously drops the rack.

In ordinary garages a great number of jacks are required because themechanics will raise a car by a jack or jacks which they leave in placeto serve as trestles. Where the garage is very small andonly one car ishandled at a time there is no objection to the practice but where thereis a volume of business it is extremely convenient to employ trestlesnot only because they are much more rigidthan a jack but primarilybecause of the relatively great expense of the elevating jacks and thesaving that is naturally had by reducing the number of jacks required.

Adjustable stands or trestles are themselves well known and old and itis quite customary for these adjustable stands to employ a base, a rackvertically slidable in the base, a pawl to engage the rack, and oftenmeans of some kind connected to the pawl to lift it out of engagementwith the customary rack or ratchet teeth, the pawl frequently beingspring pressed. The present invention therefore is limited to details,primarily of the integral pawl and handle. 1

In the drawing Figure l is a side elevation with the near arm of thehandle broken away.

Figure 2 is a top plan view.

Figure 8 is a central vertical section thru the pawl.

The body 10 of the trestle is formed of a single casting the top ofwhich is a hollow parallelepipedon each of the six faces of erably by asingle pivot pin 16 passing thru the arms, the ears, and the pawl.

The top face 17 and the bottom face 18 have I alined rectangularopenings 19 and 20 and the bottom face'18 forms'the top piece'of ahollow four-sided pyramid, the four sloping bars 22 of which are anglepieces and the four bottom members 23 of which are flats, the

plan of .the bottom being square'in outline as is the top of the base,but I prefer that onl the four corner portions 24 shall touch floor orother support.

The alined holes. 19 and 20 quite snugly receivethe rack 26 there beingjust suflicient play to enable the rack to have proper verticalmovement. This closeness of fit is highly the advantageous because itenables the; trestle to form a substantially rigid support for theautomobile. The reenforcing top flange 27 extends across the entirefrontoand a portion of the sides edge.

The'rack 26 like the body 10 is a one-piece casting, the stem beingH-shaped in cross section with the ratchet teeth 28 on one of the twoparallel flanges and the saddle or head 29 being of conventional typewith the usual retaining ledges 30.

By having the axis of the pivot in the location shown in the drawing wehave an advantage of great importance because the center of gravity ofthe handle portion of the pawl casting is about in line with the frontto strengthen the casting at this face 31or beyond the plane of itsouter surheld at a very convenient location and in raising the handlethe mechanic performs two simultaneous operations, he releases the pawlallowing the rack to fall and he lifts the entire trestle because theflat sides 32 of the short transverse pieces or lugs which connect thepawl on either side with the arms 14 en,- gage the sloping rear face 33of the ears 11, and in this way the handle 15 forms the most convenientmeans possible for the transporting of the trestle from place to place.In order to reduce the strain on the handle caused by lifting thetrestle the arms may be 36 of the rack-26 between the web and flanges,

and I insert a'bolt 37 thru the web 38 after proportioned to engage thereinforcing flange 27 when the handle 15 is raised and the flange willthus act as a fulcrum in tipping the jack when it is desired to move itto another potransport the trestle by means of the handle I provide alug 35 integral with one of the side faces to extend inward into thecentral rack receiving space, the lug being sufficiently short andnarrow to fit in the slot or groove assembly and then apply a nut 39,preferably hammering over thebolt threads to prevent loss of the nut. Onraising the rack by its saddle the bolt engages the lug and the entiretrestle may be carried in this way.

In operation the car or other thing to be elevated and held raised isfirst lifted in ordinary manner by a jack but to a position slightlyhigher than wanted. The trestle which is carried by its handle 15 isslid under the axle or other portion of the car and the handle dropped.The rack is now raised by hand almost into engagement with the portionto be held and at such time the weight is transferred to the trestle bythe lowering of the jack which is now free for other work.

It will be noted that in raising the rack the pawl acts precisely as aspring pressed pawl would, allowing free movement of the rack upward butpreventing movement downward. To release the load it is necessary thatthe lifting jack again be used, this being the usual practice withtrestles of all kinds.

WV-hat I claim is: 1 I

1. A trestle consisting of a base, a rack vertically slidable in thebase and having ratchet teeth, a pawl pivoted to the base to engage saidteeth, and transportin handle means so connected to the pawl and pivotedto the base as to free the pawl from the teeth on upward movement of thehandle and to transport the trestle upon still further movement of thehandle, said handle being on one side of said rack and said pawl beingon the other side, and means on the base for preventing the handle fromengaging the rack in any position. v

2. A handle-pawl assembly for a trestle consisting of a pivoted pawl, ahandle parallel to the pivotal axis of the pawl and connected thereto bya pair of arms extending from opposite sides of the handle to the pawlto form a'substantially rectangular frameto receive inthe openingthereof a rack support. 3. In an "automobile trestle, a base consistingof a standard having a vertical opening therethru, a racksnugly slidablewithin said opening, a pawl engaging the rack teeth, and

means extending on opposite sides of the standard forming arms pivotedwith V and connected to the pawl, lugs on said arms, and

means connecting the free ends of the arms disengaged so that the entiredevicemay -be thereafter tipped and transported by means of said handle.

4. The device of claim 3 in which the transverse handle portionconnecting the arms is on the opposite side-of the device from the rackteeth, and forms a transporting bail for the trestle. v Y

5. The device of claim 3 in which the transverse member connecting thearms is on the opposite side from the rackteeth and the pawl is pivotedon an axis to one side of both theteeth and thegtransverse handle.

6. In an automobile trestle, a base having a sloping side, a pawlpivoted to the base adjacent the sloping side, a handle for moving thepawl, and a transverse member connecting the pawl and handle, saidtransverse member being so located that when the handle is lifted tofree the pawl the transverse memher will engage thesloping side of thebase whereby the pawl handle becomes the handle for the base.

7. A handle-pawl assembly for a trestlev consisting of a pawl, atransverse handle portion and a pair of spaced arms extendingfromthehandle portion to the pawlto form a hollow frame to receive in theopening thereof a rack support, said pawl being fixed with respect tosaid arms.

8. A handle-pawl assembly for a trestle consisting of a pawl havingpivoting means, a transverse handle portion parallel to said pivotingmeans and a pair of spaced arms extending from the handle portion to thepawl pivoting means to form a hollow frame to receive in the openingthereof a rack support, said pawl extending into said-opening and in thesame direction as said arms and being fixed with respect to said arms.

In testimony whereof I affix my signature.

TIOO

